MOSCOW (AP) — Russia could expand arms sales to Iran and revise the terms allowing U.S. military transit to Afghanistan if Washington launches a strike on Syria, a senior Russian lawmaker said Wednesday.

Alexei Pushkov, the Kremlin-connected chief of the foreign affairs committee in the lower house of parliament, told lawmakers that Moscow hopes the U.S. will back Russia’s proposal for Syria to put its chemical weapons under international control for their subsequent dismantling.

During Wednesday’s Russian parliament debate of a resolution on Syria, Communists called for an increase in sending Russian weapons to Iran and a revision of the contract allowing the U.S. military to go over Russia to get to Afghanistan.

Pushkov said such actions now would be premature, as Russia and the U.S. are working to find a diplomatic solution to the Syrian crisis. Still he warned if the “party of war” prevails in Washington, Russia should consider those moves.

The lower house, the State Duma, unanimously passed a resolution warning that a U.S. attack on Syria would trigger an “irreversible humanitarian catastrophe” and calling for a peaceful settlement of the crisis.

President Vladimir Putin is set to meet with Iran’s President Hasan Rouhani in Kyrgyzstan on the sidelines of a security summit later this week.

Putin’s spokesman Dmitry Peskov on Wednesday denied a media report that the Kremlin had decided to sign a new deal to deliver air-defense missile systems to Iran, Russian news agencies said.

The business daily Kommersant had made the report, citing “a source close to the Kremlin.” The deal would replace a 2007 contract that Russia scrapped in 2010 under U.S. and Israeli pressure.

The new deal would envisage the delivery of a different weapon, the S-300 VM, also known as the Antey 2500. That missile system has a shorter range and lower velocity than the S-300 PMU but it’s still a very potent weapon.

Kommersant said Russia may also sign a contract to build a second reactor at Iran’s nuclear power plant in the southern port of Bushehr.